CineCalidad. Fred Martin is a Southern spy. A northern dispatch bearer is captured, the signature to his messages is forged, and Martin is sent on the dangerous mission of luring the Northern troops into an ambush. He accomplishes this and a terrible battle results, in which the Federals are driven back. The work of Martin is so damaging to the North that plans are laid for his capture, and John Bruce, a secret service man, is assigned to the task.